Electron Beam and Gamma Radiation Dose Dependency on the Degradation Products of Polytetrafluoroethylene (PTFE)

Madhukar Katakam

Abstract

AbstractGamma radiation induced degradation phenomena of polytetrafluoroethylene (PTFE) in the form of granules has been studied. The Electron Spin Resonance (ESR) technique was used to study radical generation and behavior under different conditions. The ESR spectra of PTFE irradiated at low or very high doses of irradiation were doublets, characteristic of peroxy radicals. Similarly spectra at different temperatures are also doublets. In order to study nature of free radicals, the g-values are calculated under different conditions and reason for variation in g-values is discussed. The PTFE irradiated with electron beam (ebeam) to 10 Mrad radiation dose contain some latent hyperfine structure in their ESR spectra. The hyperfine pattern was due to radicals ~CF2-ĊF2~ and/ or ~CF2-CF2~OO as revealed by computer simulations. The Fourier Transform Infrared (FTIR) spectra has shown the formation of functional groups such as -C=O, -COOH and -COF groups with the increase of radiation dose. The decrease in -C-F stretching band intensity and the increase in -CF2 group intensity is observed.Keywords: Electron spin resonance (ESR), polytetrafluoroethylene (PTFE), gamma radiation, electron beam, degradation studiesCite this ArticleS. Ramesh, A. Raju, D. Madhuri, B.Sanjeeva Rao, K. Madhukar. ElectronBeam and Gamma Radiation DoseDependency on the Degradation Productsof Polytetrafluoroethylene (PTFE)Research & Reviews: Journal of Physics .2019; 8(1): 104 114 p.